keyof语法

interface Person {
    name: string
  age: number
  gender: string
}
class Teacher {
  constructor(private info: Person) {}
  getInfo<T extends keyof Person>(key: T): Person[T] {
    return this.info[key];
  }
}
const teacher = new Teacher({
  name: 'dell',
  age: 18,
  gender: 'male'
});
const test = teacher.getInfo('name');
console.log(test);
type Name = 'name'
const abc: Name = 'hello' //error
const abc: Name = 'name'